I coach dozens of novice cyclists each season, and I’m constantly reminded how difficult it can be to ride well without a thorough understanding of your bike’s gears. The following tips will help you ride faster and lower your risk of an untimely mechanical meltdown.
The drivetrain includes every part of your bike that helps move it forward—starting with the chainrings, crankset and pedals in front to the cassette and cogs in back. The chainrings are bolted to your crankset, and the pedals attach at the end of the crank arms. Most road/tri bikes have two or three rings with 30 to 53 teeth on them. The more teeth, the harder it is to pedal. Standard cranks usually come with 53 teeth on the big ring and 39 teeth on the small ring, while compact cranks offer a more climbing-friendly 50/34 pairing.
The cassette (aka cog set) is attached to your rear wheel hub. Cassettes usually have 8 to 11 cogs with between 11 and 28 teeth, but unlike the chainrings, the fewer teeth, the harder it is to pedal.